Packaging hygroscopic materials



Feb. 4, 1947. v w, H. GRAEBNER Erm. 2,415,387

PACKAGING HYGRSCOPIC MATERIAL Filed Jan. 24, 1944 all/111141111, v

Patented Feb. 4, 1947 UNITED sTA'lrlss4 PATENT oFFIcE Winfred H. Graebner, Neenah, and Russell C. Flom, Mcnasha, Wis., assignors to Marathon v Corporation, a corporation of Wisconsin Application January 24, 1944, Serial No. 519,524

12 Claims. (Cl. 20G-46) l e p 2 This invention relates t0 packaging of hygrO- container,l it is necessary to use an inner `celscopic materials with laminated sheet materials. lulosic sheet 3 presented o-n the interior of the More specifically, this invention relates to packpackage which is plasticized with a suitable inages made of sheet materials havinga plasticizer gredient such; as polyhydric alcohols, glycerol, incorporated in the innermost sheet which is 5 invert sugars,v sorbitol, water, phthalic acid esretained or sealed in the sheet byspecial coatters, mineral cils, organic acids of phosphoric ings provided on the surface of the sheet preacids and other known plasticizers suitable for sented or arranged on the interior of the packcellulosicsheets in amounts from 0.5 to 100% by age to prevent substantial loss or escape of., the weight of the sheet, depending upon'the degree plasticizer by contact of said sheet with the pack- .l0 of pliability desired. When Water or moistureaged hygrcscopic materials. Y sensitive sheetmaterials, such as glassine or kraft `Further details and advantages of the invenpaper, are used as the innermost sheet which is tion will be apparent from `the following specipresented on the interior of the package the plication and drawing wherein l ability and strength of such sheet materials are Figure 1 is a cross-sectional view of a laminat- V15 seriously impaired 1113011 Substantial loss or esed sheet used for making packages in accordance cape of their plasticizer content after contact' with our invention, y Awith hygro'scopic materials in the package.

Figure 2 is a sectional'view of a package utiliz- When such sheets are brought into direct con-v ing the laminated sheet material illustrated in tact with hygrcscopic materials, such as dried Figure .1, and y 20 milk, dehydrated soups, malted milk prepara- Figure 3 is a crosssectional View of another tions and the like, the hplasticizer therein will be modification of a laminated sheet material used remOVed and absorbed by the hygroscopic mates-P for making packages in accordance with our inrial at a very rapid rate, so that in time the sheet vention. 3 presented on the interior c f the package and Referring to the drawing, Figure 1 illustrates 25 in contact with the packaged hygroscopic matea laminated sheet material adapted for paekrial will become brittle, lose its 'strength and will aging hygroscopic materials in accordance with rupture on handling, thus resulting in loss of' our invention. Such sheet material is made of the COIltentS 01 detelratn thereof. an outer sheet l of any suitable fabricated sheet In Order t0 aVOd this dielllty. We Provide a material, such as paper, metal foil, regenerated 30 continuous protective barrier coating of4 suitable cellulose, cellulose acetate, rubber hydrochloride, OOmDOstOn and thickness, indicated by nuethyl cellulose, Woven textiles 'and other eommerel 4 in Figure 1. 0n the Surface 0f the inner mercially available fabricated and synthetic Sheet 3 Which is presented on the interior of the sheets, foils and lms. Sheet l is laminated to final package made frOm 0111 Sheet material. a second cellulosic sheet 3 by any suitable adhe- 35 This layer may be formed of a moisture-proof, sive 2, preferably thermoplastic incharacter, vapor-proof and thermoplastic coating film or such as waxes, resins, lacquers and the like. We y coating, such as paraffin Wax containing about prefer to laminate sheets and 2 by means 0f 1 to about 30% .by weight of rubber or other microcrystaume waxes 01 pafaddwax t0 Which elastomers such as isobutylene polymers; micromdy be added rubber gums remsnd O the 40 crystalline waxes alone or containing added inisigilblal 01' lmformng Ingredients gredients such as aluminum stearate in amounts Laminated sheet materials of the character frgix arout 1 to ribopt t2 (11% gy Welghtgulllns' described are particularly adapted for, making re s acquers c .orma e ru ber ethy1'..u' exible containers or bags of an .t b1 4- lose and the like. It 1s advantageous to utilize Yima econ D thm ist' n h tibi t f struction for packaging hygro'scopic materials. a' OP S 10a d ea seaa e ype 0 layer In order that `such packages maybe handled, asslst fomdtlon of 'de amswhenthe package shipped and stored without deterioration of the 15 Sealed as Wm be explamed later' The barner. contents and breakage or damage to the sheet lm 4 serves to retain or seal in the plasticizer materials used it is important that the packaged 50111 the sheet 3 So that it will not escape or be hygroscopic materials do not Substantially abremoved substantially from the sheet `2 when sorb any components; in the sheet materials so a package is formed such as illustrated in- Figaszto change the original physical characteristics ure 2.' .The inner barrierflmll forming the inofsuch sheet materials. y For example, in order ter'iorsurfae of the package will thus substanto provide a very flexible and pliablel type c1255 tiallyppreserve the f'leriileilitv, pliability and strength of the inner sheet 3 and prevent its deandos? f ponent are `given in pounds per rearn (4130- vnumeralsv I0, l2 and i3, united by any desired suitable adhesive layers il and I2, respectively, and provided with a barrier or protective layer I4 on the face which is presented on the interior of the package made from such sheet material.A

This barrier layer I4 is formed from similar compositions as layer 4 previously described. The innermost sheet I3, for example, maybe glassine or kraft paper containing' a plasticizer, such as glycerlne, which serves to impart flexibility and pliability to the sheet, or aplasticized sheet of regenerated cellulose. The protective layer i5 will prevent substantial loss of the plasticizer in the package as previously explained.

Packages of hygroscopic materials made from our sheet material as herein disclosed will protect the contents for unusually long periods of time against deterioration and spoilage. At the same time the container will notl lose its strength, flexibility and protective value as the sheet material components are preserved against deterioration for the reasons previously explained.

Having described the essential features of our invention and the advantages thereof, We claim:

l. A package of hygroscopic material comprising a container Wall formed of laminated sheets, the innermost sheet adjacent thepackaged iiygroscopic material containing a plasticizer, and a continuous thermoplastic barrier film comprising microcrystalline wax and of about 20% of the weight per ream of the combined sheet, on the face of said lsheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial Withdrawal or loss of said Couromzm Example 1 v Pounds weight per ream 1. Kraft paper i 30 2. Microcrystalline wax M. P. 145-7"y F 15 3. Regenerated cellulose l L 20 4. Coating by wt. 3% aluminum stearato, 5%'

ester gum, 92% microcrystalline wax M. P. 145-'7 F 15 Total 80 l Example 2 Kraft paper 30 `Microcrystallin'e wax M. P. 145-7 F Plasticized glassine. 24 Coating by Wt. 3% aluminum stearate, 5% ester gum, 92% microcrystalline wax M. P. 145-7" F...v s i6 rotar l 986 I i Ezrarliple 3 -K Wet-strength kraft paper 33 'Microcrystalline wax M. P. 145-7 F f 16 Regenerated cellulose Y 20 Coating by wiz-3% aluminum stearate, 5% ester gum, 92% microcrystalline wax M. P. 14s-7 1i*T v 16 Total 85 Our laminated sheet materials may be used for general packaging purposes and also may be vconverted into suitable receptacles, containers, bags, tubes, pouches. and the like. l As illustrated in Figure 2, bags may be made from our sheet material so as to present the barrier layer 4 on the interior surfacethereof with which thehygroscopic material ,8 is brought into contact. The

bag maybe formed of any desired. known construction. In the construction shown'in Figure 2 the upper seam portions 5 of the bag are folded so as to bring the coating layer 4 into face to y trated in Figure 2, or by the vuse of adhesives applied at the seam areas.

plasticirer and embrittlement of said innermost sheet. I

` 2. A package of hygroscopic material comprising a container wall formed of laminated sheets. the innermost sheet adjacent the packaged hygroscopic material consisting of a cellulosic material and containing a plasticizer, and a continuous-barrier film comprising microcrystalline Wax and of about l5 lbs. or more per ream on the face of said sheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

3. A package of hygroscopic material comprising a container wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material consisting of glassine and conicent said hygroscopic material to prevent sub- It is to be understood. that our invention i`s not restricted to any speciiic type of package or con- -tainer-construction. Our sheet material may be utilized in any type of known package or container construction, the sheet material being dis-V posed and arranged so as to present theubarrier layer 4 on the interior of the package orcontainer y forpackaging -hygroscopic materials.

We may utilize many different combinations of laminated sheet materials in producing containers `and packages in accordance with our invention.4 For example, instead of two-ply sheet materials we may utilize three or more plies of any suitable sheet materials as shown in Figure 3 by stantial withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

- 4. A package of hygroscopic material comprislng a container wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material consisting of kraft 'paper and containing a plasticizer, and a continuous barrier nlm comprising microcrystalline wax and of about l5 lbs. or more per ream on the face of vsaid sheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

' 5. A package of hygroscopic material comprising a container wall formed of 'laminated sheets.

the innermost sheet adjacent the packaged 'hygroscopic material consisting of regenerated celnous barrier film comprising microcrystalline Wax and of about lbs. or more per ream on the face of s aid sheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

6. A package of hygroscopic material comprising a container wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material containing a plasticizer, and a continuous barrier film of about by Weight per ream of the combined sheet comprising microcrystalline wax on the face of said sheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

7. A package of hygroscopic material comprising a container Wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material consisting of glassine and containing a plasticizer, and a continuous barrier film of about 15 lbs. or more per ream comprising microcrystalline Wax on the face of said sheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

8. A package of hygroscopic material comprising a container wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material containing' a plasticizer, and a continuous barrier film of about l5 lbs. or more per ream comprising microcrystalline wax and aluminum stearate on the face'of -saidsheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

9. A package of hygroscopic material comprising a container Wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material containing a plasticizer, and a continuous barrier hn of about 15 lbs. or more per ream comprising wax and rubber on the face of said' sheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial Withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

10. A package of hygrscopic material comprising a container wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material containing a plasticizer, and a continuous barrier lm of about 15 lbs..or more per ream comprising wax and about 1 to about 30% by Weight of rubber on the face of said sheet presented on the interior of the package adjacent said'hygroscopic material to prevent substantial withdrawal or loss of said plasticizer and.embrittlement of said innermost sheet.

11. A package of hygroscopic material compris-l ing a container wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material containing a plasticizer, and a continuous barrier lm of about 15 lbs. or more per ream comprising wax and an elastomer on the face of said sheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial Withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

. 12. A package of hygroscopic material comprising a container wall formed of laminated sheets, the innermost sheet adjacent the packaged hygroscopic material containing a plasticizer, and a continuous barrier film of about 15 lbs. or more per ream comprising Wax and a modier on the face of said sheet presented on the interior of the package adjacent said hygroscopic material to prevent substantial withdrawal or loss of said plasticizer and embrittlement of said innermost sheet.

`WINFRED H. GRAEBNER. RUSSELL C. FLOM.

REFERENCES CITED The follovving references are of record in the iile of this patent: 

